Method of providing solvency induction



July v28, 1942. J. E. HARVEY, JR 2,291,333

METHOD OF PROVIDING SOLVENCY INDUCTION Filed Aug. 14, 1940 FES/00 l JOLI/[N7 Patented July 28, 1942 METHOD OF PROVIDING SOLVENOY INDUCTION Jacquelin E. Harvey, Jr., Atlanta, Ga., assigner of one-half to Southern Wood Preserving Coinpany, East Point, Ga., a corporation of Georgia Application August 14, 1940, Serial No. 352,655

(Cl. 19E-53) 1 Claim.

This invention relates to the production of solvents.

More especially, the present invention relates to the production of solvents from hydrocarbons containing oxygenated compounds.

An object of the present invention is the production of solvents of lower boiling range from hydrocarbons of higher boiling range, said hydrocarbons characterized by content of oxygenated compounds.

Another object of the present invention is the production of solvents of lower boiling range from liquid and solid hydrocarbons of higher boiling range, said liquid and solid hydrocarbons being characterized by the presence of oxygenated compounds.

Still another object of the present invention is the conversion of liquid and solid hydrocarbons, to the extent of a substantial percentage, into solvents of lower boiling range; said liquid and solid hydrocarbons being characterized by content of oxygenated compounds.

A more specific object of the invention is the conversion of tars of aromatic content and fractions thereof, to the extent of a substantial percentage, into lower boiling solvents of superior quality. Said tars and fractions thereof being characterized by the presence of oxygenated compounds.

Still another object of the present invention is the subjecting of tars of aromatic content and fractions thereof characterized by oxygen content to the step-wise action of hydrogen while contacting a catalyst adapted to influence -the decomposition of said oxygenated compounds.

The tars forming suitable starting materials for the process of the present invention are tars of oxygen content and are derived from coal, wood, petroleum, gas and gases, and are characterized by aromatic content; more specifically gas house tar, water gas tar, tars derived from coal, as for instance, coke oven tar, and low temperature tar; "aromatic tars of petroleum derivation, including gases. Selected fractions of the foregoing tars, as for instance, pitch or high boiling residues or fractions thereof, including stripped tars serve as suitable starting materials.

Viewed broadly, the present invention vprovides a process wherein, among other things, coal tar or the like is subjected to the action of hydrogen in step-wise manner under controlled conditions whereby the molecular complexes of the starting material are reduced, including in size, to provide if desired solvents of lowered and acterized by having directly usable solvency as opposed to the high boiling fractions (molecular complexes) yof said starting material Whose solvency is not directly usable, or partially or totally absent.

It is now found when converting tars or fractions thereof containing high molecular complexes, characterized by content of oxygenated compounds, to solvents of superior solvency, that the induction of solvency is enhanced by provision of specific means of influencing the decomposition of said oxygenated compounds contained in the starting material when under the influence of hydrogen. Y Y

The present invention provides, among other things, a method whereby tars and fractions thereof of oxygen content are converted by the action of hydrogen in step-wise manner to solvents of superior solvency, said conversion being lcharacterized by being effected in at least one cycle of hydrogen action in the liquid phase in the presence of catalytic material that influences decomposition of oxygenated compounds contained in the starting material, while under the influence of hydrogen. By the specific provision of the inclusion of a catalytic material or materials adapted to influence decomposition of said oxygenated compounds, while subjected to hydrogen action, the process which induces solvency and converts aforenamed tars and fractions thereof of oxygen content in step-Wise manner into superior solvents, is enhanced.

Included among those materials adapted to iniiuence the decomposition of oxygenated compounds, while holding the starting material containing said oxygenated compounds under the influence of hydrogen, are halids, halogens and derivatives thereof including substitution and addition products thereof.

The invention will be understood from the following description of illustrative steps comprising various methods of securing the objects of the invention, when read in connection with the accompanying drawing wherein the figure is a diagrammatic sketch of an apparatus for carrying out a form of the process of the invention and wherein the nature of the step carried out in each chamber and the contents thereof are indicated by legend.

Example 1.-A high residue creosote having substantially 48% boiling above 355 C. and substantially 2% coke residue is charged to a high pressure autoclave and subjected to the action of hydrogen at 200 atmospheres pressure and a controlled boiling range, said solvents being chartemperature of 400 C.; catalyst, molybdenum twice beneiiciated pitch is distilled to an upper limit of 210 C. to provide a distillate as an intermediate starting material for the solvents of the present process. The distillate is then subjected to the action of hydrogen at 535 C. and a pressure of 200 atmospheres. The beneiiciated distillate will be found to have a solvency in excess of its intermediate parent material and will be further characterized by increment of low boiling fractions in excess of fractional increment Y in the higher boiling range.

'The thus beneficiated material will be found to i have an increased solvency as compared to its Y intermediate starting material, further characterized by having an increment of low boiling fractions in excess of fractional-increment in the higher boiling range. incidental to the above named stripping operand will beY VIn, conjunction with the decomposition influencers previously named, all catalysts effective Vin the presence of hydrogen for aforementioned purposesV are usable, as for instance, chromium,

" molybdenum; vanadium, manganese, uranium,

The residue Y ation is recycled for further solvent production;

The first actionof hydrogen is characterized by preferential action on the high boiling range.Y

By the presence of the decomposition inuencer the induction of solvency is enhanced. c'

Example 2.-A coal tar, specific gravity 1.1641, coke residue in excess of 8% and boiling predominantly above 190 C. is passed through a high pressure reactionV vessel while ysimultaneously flowing hydrogen therethrough at a temperature of 410 C. and 350 atmospheres pressure. The catalyst used is molybdenum oxide and aluminum chloride. Time of reaction is 75 minutes and a iiow of hydrogen 12,000 cubic feet per barrel feedstock. The beneiiciated tar is distilled to an upper limit of 260 C. to provide the distillate as an intermediate starting material. The intermediate starting material is then passed through a high pressure reaction vessel while simultaneously flowing hydrogen therewith. The catalyst is molybdenum sulfide, and the iiow of hydrogen 6,000 cubic feet per barrel of feed stock; the timeof contact is two minutes. The beneficiated material will be found to have a solvency in excess of its intermediate starting material and will be characterized by an increment of low boiling fractions in excess of fractional incre-l ment in the high boiling range.

Example 3.-.A tar fraction of aromatic content, initial boiling point substantially 220 C. and having 50% residue in excess of 355 C.,is subjected to the action of hydrogen while contacting a cobalt sulfide-tin chloride catalyst. Reaction is carried on for a period of one hour at 410 C. and a pressure of 400 atmospheres'. The

beneiiciated material will be found to have a` lowered coke residue, specific gravity and Viscosity and a condensation of boiling points toward the loweredboiling end. The beneiiciated material is then distilled to an upper limit of 320 C. with the distillate serving as intermediate starting material'. The intermediate starting material is subjected to the action of hydrogen at a, temperature of 465 C. and a pressure of 200 atmospheres. The finally beneiiciated material will be found to have a solvency in excess of its intermediate starting material and will be further characterized by an increment of low boiling fractions in excess of fractional increment in the higher boiling range.

Example 4,- A coal tar fraction specific grav- Vity 1.23am 15% boiling at 355 C. is subjected to the action of hydrogen at 375 C. and 200` atmospheres pressure. The catalyst is vanadium sulfide and iodoform and the time of reaction one hour. The beneficiated pitch is again subjected to van identical cycle of hydrogenation. The

like.

cobalt, copperandtheir compounds as suliides or oxides; promoted or not; with or Without small amounts Vof alkali, acid, halogen, or derivatives thereof. Small amounts of halogen or halogens, as such, or incorporated with other substances may be used, effective catalysts deposited on carriers, as for instance, gels, earths, carbon', Yor the Catalysts may be used in various shapes, as f or instance, forms, extruded shapes or lengths, pellets, comminuted; mixed with other material possessing desired action ornot; with or without material effecting splitting; Acatalysts Ywith added halogen derivatives.

In step-wise action of Vhydrogen in the presentY invention, the iirst actionV of hydrogen `on the,

starting material isA characterized by reduction of coke residue, specific gravity, and. viscosity,

Y `In the iirstlcycle of. Yhydrogen action pressures intermediate starting material at least once sub-V Jected to the action of hydrogen.inQaccordancei as low as 50 atmospheres are usable as are, temperatures as low as 200 C., however, higher temperatures and pressuresare preferred, asforinstance, temperatures of VS50-450 C. and pressures of in-excess of Y200 atmospheres. Pressures and temperatures'are, however, notrestricted to any definite limitations inasmuch. as hydrogen action that reduces Ythe coke. residue, specific gravity and viscosity ofthe starting ma- Y terial will proceed at lowered temperatures and pressures. The desired temperatures and ,pressures are thosethat Will reduce coke residue, specific gravity and viscosity ina commercial manner. When using continuous operation in the first hydrogen cycle, iiows of.10,00015,000l

cubic-feet per barrel feed stock have proven satisfactory, however, higher and'lower gas flows have proven effective.V Y l Y 'Y i In the lastcycleA ofhydrogen action, as comprising a part of the present invention, for a given coordination of temperature and-pressure as compared to the first cycle, the hydrogen flowjV 200 atmospheres land temperatures chosen from the range between' 30G-750 C.`

Aromatic ers.' @festem derivati;

produced fromgas or gases serve as suitable startingV materialsf'ars or fractions A thereof, at least once refined ,byhydrogenor other means Y valso serve as startingrmaterials;

in the appended `clairris is meant Athe starting pr to the present process.

In the last cycle of hydrogen'action pres-Y Other catalysts or materials influencing splitting cr decomposition may be used in conjunction with aforesaid sulfide catalysts.

In both cycles of hydrogen action the present process is predicated on so controlling the reaction conditicns that ring structures are not opened with the subsequent formation of liquid chain or paraffin structures to the extent that the solvents of enhanced solvency of the present invention are impossible of manufacture.

In the first cyclic action of hydrogen action, conditions are so controlled as to induce no substantial percentage of carbonaceous increment. When utilizing most of the starting materials, the first action of hydrogen is further characterized by the depolymerization of high molecular complexes. By the term high molecular complexes is meant those high boiling fractions especially susceptible to thermal degradation.

In the second cycle of hydrogen action periods as short as one minute at operating conditions have proven beneficial, however, longer periods may be used, as for instance, several minutes. As a general rule, it may be said that the time element in the second cycle is that period necessary to provide iinal increment of low boiling fractions in excess of fractional increment in the higher boiling range, and to induce solvency.

The hydrogen supply used in the present process may come from any convenient source, as for instance, by the disassociation of methane. If desired, any diluting gas may be used in connection with the hydrogen.

When the starting material has been subjected to the rst cycle of hydrogen action that reduces coke residue, specific gravity and viscosity, the stripping of the beneiiciated mass may be effected at any point desired as for instance, at 200 C., or higher, or lower. Generally the point of stripping is determined by the boiling range desired in the product flowing Afrom the final action of hydrogen in the second cycle.

Within the limits of the boiling range of the finally beneficiated material, solvents and/or plasticizers may be fractionated therefrom, as for instance, to provide substitutes for the boiling range or ranges of any of the following:

Degrees Centigrade Benzol 78-120 Toluol U-150 Hi-flash naphtha 150-200 Heavy naphtha 150-290 Plasticizers 160-360 ing material can be made to substantially finally disappear.

Starting materials include tars and fractions thereof derived from wood, coal, and petroleum including gases of carbon content; as for instance, wood tar, pine tar, coke oven tar, gas house tar, water gas tar and synthetic aromatic tars derived from petroleum sources including gases containing carbon.

Starting materials previously subjected to the action of hydrogen are suitable starting materials.

In the disclosures herein made the removing of loW boiling fractions by gas movement or pressure release is considered the equivalent of distillation.

When reference is made to high molecular complexes contained in the starting material, and when the starting material contains low boiling fractions that are not -considered high molecular complexes, it is of course obvious that the high molecular complexes contained in the starting material are to a certain extent depolymerized by the solvent present.

Starting materials of the present process also include tars of aromatic content from which low boiling fractions have been removed, as for nstance, tars from which Solvent oils have been removed. Viewed broadly, the starting materials of the present process are tars of aromatic content, fractions of said tar more viscous than the starting material due to removal of low boiling fractions from the starting material, high boiling fractions and pitches.

The term coal tar as used herein means a tar produced by high temperature carbonization of coal, as for instance, high temperature coke oven tar or gas house tar.

Minor changes may be made in the steps of the process without departing from the spirit of the invention.

I claim:

In the production of solvents from a mixture of high temperature coal tar fractions the process which comprises: subjecting said mixture of tar fractions to the action of a flow of hydrogen in excess of about 10,000 cubic feet per barre'l material treated while contacting as catalytic materials a metal sulfide and iodoform with time, temperature and pressure so controlled as to reduce specific gravity aind Viscosity; stripping low boiling fractions from the beneficiated mass and subjecting at least a portion of said low boiling fractions to the action of a relatively low flow of hydrogen at superatmospheric pressure and a temperature selected between the range of about 465-535o C.; and continuing the phase of the process last named for such a, length of time as to provide a material of increased solvency.

JACQUELIN E. HARVEY, JR. 

